Our vet called with good news this morning, saying that Indy is negative for feline leukemia virus, FIV, and hemobart, and all his blood work looks very good. Now we don't have to keep him out of Zoe's litterbox and food anymore and can relax a bit more.
They have been chasing each other back and forth for the last half hour. She still hisses and growls if she gets cornered or feels threatened, but then will go right back to playing. They're still just working out how to play together. He bites a bit in play and I was worried about that until I remembered that Zoe and Smudge used to bite each other but they never got hurt and were good friends. I think it is also just that he's young too. They seek each other out when they want to play already and we're sure they're going to be good friends.
We can finalize Indy's adoption on Saturday and we're looking forward to making him a permanent member of the family.
He is already the same size as her although he's half her age (a few pounds lighter though). He's going to be a really big guy. These are the best pictures I could get of them together because they don't really ever stop moving.